Delivery device and method for its operation

ABSTRACT

Provided is a method for operating a preparation delivery device wherein the device comprises a) a container for the preparation having, or being prepared for the arrangement of, an opening, b) a mechanism operable to deliver at least part of the preparation in the container through the opening, c) attachment means for connection of the container to the mechanism and d) a sensor system arranged to detect at least one predetermined property of the container or its content. The method comprises transmitting radiation towards the container position or a part thereof to allow the radiation to be affected by the container position, receiving at least a part of the affected radiation from at least an area part of the container position in a non-imaging way and comparing the characteristics of the received radiation with a predetermined characteristic representative for the predetermined property to establish whether or not the predetermined property of the container is present.

FIELD OF THE INVENTION

[0001] The present invention relates to a preparation delivery deviceincluding a container for the preparation having or being prepared forthe arrangement of an opening. The device also includes a mechanismoperable to deliver at least part of the preparation in the containerthrough the opening. Attachment means connects the container to themechanism. A sensor system is arranged to detect at least onepredetermined property of the container or its content. The inventionalso relates to an operation method for such a device, to containers orcontainer system for use in the device and a marking system or analyzingdevice relating to components of the device.

BACKGROUND OF THE INVENTION

[0002] Injection devices based on a separate delivery mechanismattachable to replaceable containers have found widespread use in manyareas, such as medical delivery systems. This use is due to theflexibility and economy contained in the possibility of providing areusable pump type device with more or less advanced machinery forpreparing, dosing, controlling and monitoring the injection procedure.The replaceable container features can be limited to those necessary forsafe confinement and simple expulsion of the pharmaceutical, featureswhich furthermore may be adapted to each individual preparation type.

[0003] Delivery devices are known for use in more permanent set-ups,e.g. for hospital treatment situations. Such setups include few designrestrictions. Also, the pump part can be highly sophisticated in view ofmotorized manipulation means, processor controlled operation and datacollection as well as possible interfacing against other availableinstrumentation. Often, the design freedom is also utilized to make thepump part compatible with one or several existing or standardizedcartridges, syringe or injection device types, thereby increasing theapplication range for the instrument and reducing adaptation costs forthe cartridge part.

[0004] For ambulatory purposes, the design limitations are more severe,especially for self-contained devices without connectable support. Sizeand weight restrictions place limitations on the number andsophistication degree of functions possible to include. Automation as analternative measure for increasing safety and avoiding misuse issimilarly restricted by the added motorized means and operationrepertoire by limited capacity of energy storage means. Although handyand portable injectors may be devised with the minimum of supportfeatures necessary to safely control all the above-said requirements andproblems in the hands of a skilled operator, a general trend inlong-term medication is to place the administration responsibility onthe patient himself, also in the case of children or disabled persons,e.g. by use of pen-type injectors. A high degree of automation andcontrol is then desirable to avoid mistakes, not only at the mereinjection steps but also the critical initiation and preparation steps.Patients dependent on daily administrations also have a legitimate needfor convenience and devices discrete enough to be carried around indaily life. The contradictory requirements on highly sophisticated andyet small and convenient devices need to be met by new technology.

[0005] Delivery devices both for permanent and ambulatory use need areliable sensor system for container control and verification in broadsense The mere range of container types attachable to the generalpurpose pumps for stationary use in itself creates a control problem.Also, for portable devices, the option of patient self-administrationrequires a fail-safe control and the widespread distribution of pumpsand containers requires corresponding precautions against intended orunintended misuse or abuse. The reliance on automation for mostfunctions in the devices assumes an input to the processor of, forexample, the presence of a container, check of its condition,verification of its non-used status and information of container type,content, concentration, expiration date etc. It may also be desirable toinput individual patient data and administration schemes. Even when thepump device is intended only for a single or a few container types orcontents the pump should be inoperable except for with these containers,and also when intentional efforts are made to circumvent the safetysystem.

[0006] It is clear that the desirable controls may be of quite varyingnatures. Pure information may be transferred from a machine readablemarking on the container to the device. Such information may be totallyunrelated to the container, as in the case of patient data or a securitycode, or related thereto, as in the case of markings representingcontainer preparation type and volume. Control of physical containercharacteristics, such as size and orientation, and functionalproperties, such as presence of preparation and plunger position, mayrequire a non-standard design of the container with special features forsensing, a highly sophisticated all purpose monitoring system ormultiple specialized sensors for each feature to be detected, all ofwhich alternatives are incompatible with the abovesaid general demandsplaced on stationary or portable pump systems.

[0007] Common information carrying marking techniques are not suitablefor the purposes outlined. U.S. Pat. No. 4,978,335 and InternationalPatent Document WO 93/02720 suggest, among other things, the use of abar code and a bar code reader for similar purposes. Bar codes do notcarry much information on a given surface, require a reader ofsignificant size which can not conveniently be housed in small devices,utilize complex radiation systems and the code, as such, is easilymanipulated and, hence, not safe against forgery. Finally, the system isnor usable for sensing any container characteristic other than thespecified coding. Similar disadvantages and restrictions are presentwith marking systems based on reading of alphanumeric characters,magnetic strips, etc.

[0008] Sensors for physical or functional container properties seem tobe scarce in the prior art. Systems based on switches, as represented byU.S. Pat. No. 4,838,857 activated by a container when in properposition, give a highly inflexible sensing system unless a multitude ofswitches are arranged and a system susceptible to wear andcontamination. Also, systems based on interlocking of mating structures,as exemplified by EP 549 694, are inflexible, unprecise and easilycheated and, to the extent special key features are provided on thecartridge part, not compatible with standard containers. Knownprinciples seem to be highly specialized, easily manipulated and notadaptable for a complementary information reading.

[0009] Accordingly, there remains a need for a sensing system able tomeet the various demands in medical delivery devices while beingcompatible with the typical restraints in these applications. Althoughthe present invention has a more general utility, it will mainly bedescribed against this background.

SUMMARY OF THE INVENTION

[0010] A main object of the present invention is to offer a sensorsystem limiting the abovesaid disadvantages associated with the priorart. A more specific object is to offer such a system useful in medicaldelivery devices. Another object is to provide a system suitable for usein portable devices by having small size, low weight and low energyconsumption. A further object is to provide a reliable and a not easilymanipulated system. Still another object is to provide a system able tosense marked information in a reliable way. Another object is to providea system able to sense a variety of functional properties. Yet anotherobject is to devise a system able to sense both marked information andfunctional properties. A further object is to offer a sensor system thatis highly compatible with automation and microcontroller processing ofits output.

[0011] These objects are reached with a system having thecharacteristics set forth in the appended claims.

[0012] Several of the above objects may be achieved by utilization inthe present invention of the general principle of transmitting radiationtowards the object to be sensed and receiving for further analysisradiation affected by the object. Mechanical contact between sensor andobject need not be present, thereby increasing positioning and useflexibility while reducing problems with wear and contamination.Flexibility is also provided by the variety of mutualtransmitter/receiver positioning possibilities available. By detectingfunctional object properties on the basis of a comparison betweenradiation received and a predetermined representation thereof, thesystem becomes highly flexible and adaptable to many object properties.Also, the same receiver may be used for detection of several properties.The criteria for defining the predetermined representation may beunknown to the user and accordingly difficult to satisfy by unauthorizedindividuals.

[0013] Use of non-imaging or even de-focused radiation has severaladvantages. Very simple and cheap components can be utilized. A largedetection area in both width and depth facilitates positioning of thecomponents and allows radiation received from different depths to affectthe response with equal significance, of value, for example, withtransparent objects such as in common medical containers. In sensing offunctional properties, this flexibility, as well as the possibility tolet every interface surface affect the response, give a broad range ofpotentially detectable properties which may be covered by a single or afew receivers and also permit monitoring of dynamically changingproperties. In sensing marked information, a large detection area may beemployed to reduce misreading due to contamination, increase informationamount by using multiple analog response levels in addition tostructures in the marking and strongly improve security by using markingfeatures not readily detectable by visual inspection. The latter pointmay be further improved on by using radiation in non-visible frequencyranges. It is clear that the same system can be used for sensing bothfunctional properties and marked information, typically needed inmedical delivery applications, and being highly beneficial where size,weight, economy and energy consumption matter, as in portable articles.Adaptation to automation is simple owing to the few componentsnecessary, the simple driving thereof, the compatibility with scanningactions or dynamic operations and the easy processing also in real timeof a sequential output from the receiver.

[0014] Further objects and advantages will become evident from thedetailed description of the invention hereinbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIGS. 1a and 1 b show schematically active elements arranged at acartridge type container;

[0016]FIG. 2 is a diagram of an actual response in reflected radiationfrom a scanning over a plunger position;

[0017]FIG. 3 is a simplified flow block diagram of suitable electronicsfor a sensor system according to the invention;

[0018]FIG. 4 is a detailed circuit diagram for use in the electronics ofFIG. 3;

[0019]FIG. 5 is examples of labels with markings to be read by thesensor; and

[0020]FIGS. 6a to 6 d schematically show a pump device and a dualchamber cartridge in four stages of operation.

DETAILED DESCRIPTION OF THE INVENTION General

[0021] As used herein “system” shall be understood to refer to thepresent invention generally, when including its parts, such as devices,methods of operation, marking principles and crucial components, such aspump parts and containers.

[0022] As indicated in the introduction, the sensor system and markingprinciples thereof described herein may be used for a variety ofpurposes within and beyond the medical area and for any type ofpreparations, such as chemicals, compositions or mixtures, in anycontainer and delivered for any purpose. For reasons outlined, thesystem has certain special values in connection with medical deliverydevices where the design constraints are more severe than in most otherapplications. For convenience, the invention will be described in termsof this application.

[0023] The principles of the present invention may be used for deliverydevices or systems in broad terms. The delivery means from the devicemay be an infusion channel or any conducting means, such as a tube orcatheter, a needle or cannula, or a needleless system based on a liquidjet or a particle gun with gas propellant. The container contentmaterial shall be deliverable by use of a delivery mechanism and anymaterial fulfilling this requirement can be used.

[0024] Normally, the material is a fluid and preferably a liquid,including materials behaving as liquids, such as emulsions orsuspensions. These observations relate to the final preparation, whereasother components, notably solids, may be present before finalpreparation. The nature of the container content shall also beunderstood to include medical materials in broad terms and to embrace,for example, natural components and body fluids prefilled or drawn intothe container, although most commonly the medical material is factoryprepared.

[0025] The invention may assist in solving special problems inconnection with sensitive compounds susceptible to degradation ordenaturation under mechanical stress, such as high shear forces.Compounds of high molecular weight may be of this type, high molecularweight hormones for example growth hormones or prostaglandins. Theinvention may also assist in solving special problems in connection withmedical materials requiring a preparation step immediately prior to theinfusion, typically a mixing of two or more components, which all may befluid or may include a solid as when dissolving a lyophilized powder ina solvent, such as hormones or prostaglandins.

[0026] The administration manner can also be varied within broad limitsand may include entirely continuous infusion, continuous infusion withvarying flow or intermittent infusions or injections with repeatedeither equal or varying doses. Especially when combined with automationmeans in a preferred way the administration manner can easily be variedby adaptations in software or similar control. In portable devices, theintermittent administration is common. Similarly, although deliverydevices may be contemplated also for a single dosing operation,generally they are designed for more than one or multiple individualdoses for intermittent administration.

[0027] In addition to the basic functions for delivery purposes, thedelivery system with preference may include other valuable features,such as for initiating the container and its contents, and providevarious checks and controls of both the container and the pump partelectronics and mechanics.

[0028] As mentioned in the introduction, the principles of the inventionmay be applied to delivery devices in stationary or permanent set-ups.Due to, among other factors, the simplicity provided, the presentinvention provides special advantages in delivery devices for ambulatorypurposes, especially those being autonomous with on-board energystorage, motor and processor means and, in particular, small hand-helddevices of truly portable nature.

[0029] A preferred medication delivery device according to the presentinvention can be said to generally comprise at least a container for themedication having or being prepared for the arrangement of an opening, amechanism operable to deliver at least a portion of the medication inthe container through the opening, attachment means for connection ofthe container to the mechanism and a sensor system arranged to detect atleast one predetermined property of the container or its content.

The Container

[0030] The container part shall be understood in broad sense and maytake a variety of forms such as any kind of tube, vessel, flexible bag,vial, ampoule, cartridge, carpoule, syringe body, etc. There are someadvantages in using containers that are rigid, at least at theiropenings or the part for attachment to the mechanism but preferablygenerally rigid, such as vials, ampoules or syringe bodies. There arealso some advantages in employing the invention in connection withcontainers that are at least translucent and preferably transparent atleast partially and preferably generally at the frequency of theradiation used. Common container materials, such as glass or plastic,can, with preference, be used. The container may be an integral orcomposite structure, such as including an outer casing or any othermultipart construction for closures, fixtures, protection, etc. Wheneverused herein, “container” shall be understood to include any auxiliarypart present. The container has at least one opening through which themedication passes during the main delivery operation of the device,either from the container interior to the surrounding for e.g.administration of the medication to the patient or to the container incase of aspiration of body fluids or at preparation steps such asfilling, mixing or dissolution in the container, during which operationsthe opening needs to be present. It is possible and even in manysituations preferred that certain device operations, such as labelreading, container control or initiation, take place before establishingcommunication. The opening requirement shall then be consideredsatisfied by the preparation means for creating the communication, suchas the presence of a removable closure or a pierceable or rupturablepart on the container itself as in the case of an ampoule or bag or aspecially designed part as in case of penetrable membranes or septum.

[0031] All communication may take place through one opening, forexample, with both medical passage and pressure equalization in a rigidcontainer or by delivery from a container which is flexible or has amovable or deformable part. However, nothing prevents providing furtheropenings for similar purposes. A further opening can be identical to theat least one opening but can be entirely different. Also, a furtheropening can be adapted for another purpose, such as, for example,infusion or syringe type with a movable wall or piston.

[0032] The container may be a simple bottle, vial or bag in case thedelivery device is arranged to withdraw, continuously or intermittently,metered amounts therefrom for delivery as defined. Often, and especiallyin connection with self-administration, the container type is moreelaborate and is commonly in the form of a cartridge, being thecontainer part of a syringe type of delivery system, which may be stillmore elaborate in the case of multichamber cartridges. Cartridge typecontainers shall be further described as they generally requireadditional initiation or control steps for which the principles of theinvention with preference can be exploited.

[0033] A cartridge for the present purposes may generally be said toinclude a vessel having a front part and a rear part defining a generalcartridge axis, an outlet for the preparation arranged at the front partand at least one movable wall arranged at the rear part, a displacementof which wall causes the preparation to be moved towards or expelledthrough the outlet. Vessel shape and movable wall have to be mutuallyadapted. The vessel may be designed most freely when the wall is aflexible or oversized membrane or diaphragm able to adapt by movement orreshaping to vessel internal surfaces, in which case a fluid cushion orresilient material may be needed between the wall and piston rod tosmooth out applied pressure. Preferably, however, the vessel has asubstantially constant internal cross-section, with a similarly constantvessel axis, between front and rear parts giving a generally tube-shapedvessel. Most preferably, the cross-section is of the common circulartype giving a substantially cylindrical vessel. The movable wall is thenpreferably a substantially shape-permanent, although possibly elastic,body sealing adapted to the internal vessel surface and preferably ofthe plunger type having sufficient length to self-stabilize againsttumbling during travel along the vessel. The front part outlet may be ofany known design. The front part outlet may be directed laterally forbest access in certain applications, frontal but non-coaxial with vesselaxis, or most commonly arranged frontal and coaxial. The outlet may beintegral with the vessel or in a conventional manner the cartridge frontend may be provided with an attachment therefore and before connectionbe provided with a breakable or penetrable seal.

[0034] Generally, the described cartridges need several kinds ofinitiation actions, dependent on a displacement of the movable wall, toreset the device and make possible repeated and reproducible dosingmeeting high precision demands. In its first movement, the movable wallmay need an extraordinary break-loose force after storage to overcomeboth internal reshaping resistance and an increased wall friction due toadherence or depletion of lubricant in contact points. Also, in relationto the weaker regular injection force, elastic and inelasticdeformations and tolerances have to be evened out in the movable wall,cartridge shell, outlet attachments, et cetera. The preparationsthemselves may have compressible inclusions, such as gas vesicles.Deaeration and preejection is needed to remove gas in the vesselcompartment and fill out spaces for example at the front scalings,outlet attachments and the interior of the outlet devices or needles.

[0035] Dual or multi chamber cartridge types are known e.g. forpreparations demanding a mixing of two or more components or precursorsbefore administration. The components are kept separated by one or moreintermediate walls of different known design. The walls divide thevessel into several chambers, sometimes placed parallel along cartridgeaxis but most commonly in stacked relationship along the axis.Unification of the components may take place by breaking, penetrating oropening a valve construction in the intermediate walls, for example byintroducing a pin or needle through the cartridge front, through or atthe rear movable wall or by means at the cartridge exterior (comparee.g. the cited WO 93/02720). In another known design the intermediatewall or walls are of the plunger type and flow communication between thechambers is accomplished by moving the plunger to a by-pass sectionwhere the interior wall has one or several enlarged sections or repeatedcircumferential grooves and lands in a manner allowing by-flow of rearchamber content into front chamber at displacement of the rear movablewall (compare e.g. U.S. Pat. No. 4,968,299 or WO 93/20868 and WO95/11051). The chambers may contain gas, liquid or solids. Generally, atleast one liquid is present. Most commonly in pharmaceuticalapplications only two chambers are present and typically contain oneliquid and one solid, the latter being dissolved and reconstitutedduring the mixing operation.

[0036] Initiation of the multi-chamber type cartridges requires all thegeneral type steps described, although in aggravated form due to theadditional walls and spaces present. In order to provide for efficientmixing generally a mixing space has to be allotted in addition to thespace occupied by the component volumes. Powdered components in bulkform also require the extra space contained in interstices betweenparticles. The mixing step may produce foam or gas inclusions requiringspace to settle out. Plunger type intermediate walls generally have tobe displaced at least their own length to reach the non-sealing site inthe bypass. In total, multi-chamber type cartridges require long movablewall strokes in the initiating step, both for mixing and subsequentdeaeration, and benefit in a particular way from the advantages of thecurrent invention.

[0037] Cartridge sizes may vary strongly depending on the intendedapplication and general ranges are difficult to give. Typical sizes inthe preferred self-administration application by use of portable devicesare 2 to 30 mm internal diameter and preferably 3 to 20 mm.

The Mechanism

[0038] The mechanism for delivery of medical materials through thecontainer opening should basically include at least one type of pumpingmeans that may have to be selected for the specific kind or containerand medical material used. The pumping means may include any kind ofpressure source, such as mechanical or electrolytic pressure build-up,in the container. The pumping means may also include suitable valvemeans for control, which method can be used with virtually any kind ofcontainer and any kind of product, such as transdermal delivery ofpowder, as exemplified by WO 94/24263, similar delivery through liquidjets, as exemplified by WO 94/2188, or regular tube infusion, asexemplified by WO 88/09187. Any kind of container can also be used withpumps based on peristaltic action or centrifugal action. However, forgeneral use, pumps based on controlled positive displacement arepreferred and especially such pumps based on a separate cylinder andpiston action. Such pumps are exemplified by U.S. Pat. No. 5,480,381 fora liquid jet or U.S. Pat. No. 4,564,360 for a manually operated needlebased device. The common syringe type container needs a specializedpumping system. The mechanism is adapted to act on complete syringes,having their own piston rods, by engaging and axially displacing therod, as exemplified by the initially referenced U.S. Pat. No. 4,978,335,which may be preferred when it is desired to accommodate syringes ofmany different types and sizes. Alternatively, the mechanism has apiston rod acting more or less directly on the piston of a cartridgetype container, as exemplified by International Patent Document WO95/26211, European Patent EP 143,895 or European Patent EP 293,958,which can be made smaller and more adapted portable devices. Also, dualor multiple chamber cartridges can use a similar devices for theirvarious phases, as exemplified by the initially mentioned InternationalPatent Document WO 93/02720. Although the various pump mechanismsdiscussed may include mechanical means for affecting the medicalmaterial or a piston, the means, such as a piston rod, may be actuatedby any known means, such as gas pressure, vacuum, hydraulics, springs ormanual operation. It is preferred to actuate the pump means by electricmeans, such as an electrical motor, indirectly or preferably directly,among others because of its ease of adaptation to an overall automateddevice.

[0039] The mechanism may preferably include further components. Themechanism may, for example, include special means for securing dosesdelivered, e.g. by direct metering of the medical material delivered,although it is generally preferred to utilize directly or indirectly thepump means for this, e.g. by monitoring axial displacement or therotation of a piston rod axis in a known manner. In particular, it ispreferred that the mechanism includes a control system operative toperform at least part of the above-mentioned administrative patterns,initiation of containers or cartridges, self-control or surveillance andpossible recording of operation steps conducted. Such systems are knownin the art, as exemplified by U.S. Pat. No. 4,529,401, and may bedesigned in a multitude of ways. For the purposes of the presentinvention, it is preferred that the control system drives and monitorsat least part of the sensor system and processes data obtainedtherefrom.

The Attachment Means

[0040] The minimum requirement on the attachment means is to connect thecontainer to the mechanism in such a manner as to allow the mechanism toperform its pumping function. The nature of pump and container principleselected may determine how critical is the relative positioning betweencontainer and mechanism. Generally, when the mechanism is based on aseparate pump or control valve principle with a conduit to thecontainer, the relative positioning is not critical. When the containeritself is a part of the pumping or dosing principle, as for syringe orcartridge type containers, when the mechanism directly acts on thecontainer, the relative positioning may be highly critical with directinfluence on dosing precision. In the non-critical situations, it isconceivable to have the container freely or flexibly connected to themechanism, e.g. via a tube, although preferred, at least in portabledevices, to rigidly affix the container to the mechanism as well as incase of the abovesaid critical situations. If the mechanism is generallydivided in a stationary parts, for example, including actuating means,chassis and transmissions, and functional movable parts, for example,the active part in a pump, such as a piston rod, or in a deliverycontrolling valve mechanism, it is preferred to affix the containerrelative the stationary parts, directly or indirectly, although possibleto move the container towards the mechanism during delivery. Aconvenient way of implementing the indirect relative attachment betweenstationary parts and container is to provide a housing in which at leastthe stationary mechanism parts are enclosed in relative immobility andto which housing the container is attached. When present, the housingshall be regarded as the point of reference for motions unless otherwisestated.

[0041] The above-discussed relative positioning is valid for the phasewhen the mechanism delivers medication through the with preference, anymovement for scanning purposes can be combined with movements for any ofthe above-said purposes in order to facilitate the overall device andoperation, such as a parallel initiation of a cartridge and reading andchecking thereof. Movement for any purpose mentioned may include bothaxial and rotational displacements, as understood in terms of acontainer of generally rotational symmetry such as a vial or cartridge.As an example, initiation or attraction may require an axial movementwhereas a rotational movement can be used for locking. For scanningpurposes, an axial movement may serve for both reading and control offunctional properties along the container whereas a rotational movementmay serve to read more information distributed over container mantlesurface or to shift scanning purpose.

[0042] Scanning speeds can be selected freely. The sensor system isgenerally compatible with most speeds, even stationary readings, andspeeds can, with preference, be adapted to the other purposes mentioned.Typically, the movement takes place with less than 100 cm/sec,preferably less than 10 cm/sec, and most preferably less than 1 cm/sec.Suitably, the speeds are above 0.1 and also over 0.5 mm/sec.

[0043] When a housing is present, it may be desirable to extend thehousing at least partially and preferably substantially all over thecontainer to, for example, protect the container, provide guidingfeatures to stabilize it statically or dynamically during movementthereof or, in particular, to arrange sensor means in case unlesspositioned on carriers, stationary or movable, of their own, whichhousing enclosure may also act to reduce stray radiation from thesurroundings. Certainly, the housing can be designed as a composite orunitary structure.

[0044] The nature of the physical means for actual attachment of thecontainer to the mechanism or housing is generally not critical for thepresent objects and can be of any conventional or known type, such asbased on friction, push lock, undercut, bayonet lock, threads or anyother fit.

The Sensor System

[0045] The sensor system of the invention is based on the transmissionand reception of radiation. In the preferred application, the radiationis directed towards the container or any marking thereof, although, asindicated, the principles may have a more general utility as analyticalsystems for objects generally or a system for machine readableinformation generally. In terms of the preferred application thedescription of the sensor system will be divided in the radiationtechnique, the sensor applications and the signal processing.

Radiation Technique

[0046] Initially, it shall be noted that although the transmitter andreceiver have been discussed in the present context as if discretecomponents, or integral components containing both at a mutual gapdistance, the terminology shall be understood to include “transceivers”i.e. components performing both functions, simultaneously orinterchangeably, either with the same active component performing bothfunctions or preferably, for best adaptation, with separate componentshoused within the same enclosure. Transmitters, receivers andtransceivers will hereinafter collectively be referred to as “activeelements”. All components shall be understood in a broad sense. Forexample, any component made to output a response to beam alterationsshall be regarded as a receiver. Similarly, any source for radiation,natural but preferably artificial, used by the receiver shall beregarded a transmitter.

[0047] Any kind of radiation that can be affected in a detectable way bythe container or a marking can be used in the sensor system. Preferably,the radiation is electromagnetic radiation with a suitable frequencyrange between ultraviolet and microwaves and most preferably in theoptical and infrared regions. As earlier indicated, there are securityadvantages in using radiation in the non-visible ranges. The transmittermay be a maser or laser, lamps or most preferably light emitting diodes(LED's) which are preferably used for the visible and most preferablythe infrared frequency range, such as between 300 to 3000 nanometers orbetween 500 to 2000 nanometers. Good results have been obtained in thevisible area as well as infrared in 950, 870 and 875 nanometers.

[0048] The receiver should be adapted to the transmitter and for theabove given types the receiver may be a photoresistor or better aphotodiode or phototransistor. The receiver should be adapted infrequency to the transmitter or, in case of fluorescence, to anyfrequency resulting therefrom. For both transmitter and receiverfrequency, adaptation can be made by selection of type, by use ofoptical filters or application of electronic filters. Devices notoperating in the visible range may incorporate a daylight filter toremove inadvertent surrounding influence. The specific selection ofcomponents will be dependent on which imaging principle shall be used.

[0049] As used herein, an “imaging” system shall be understood as asystem able to reproduce an object with details in at least twodimensions, normally requiring a system able to provide a resolution ofpixels, points or lines, in the object in the two dimensions, which maytake place in different ways. A “focusing” imaging method may be used inwhich a lens type system gives a true two-dimensional reproduction ofthe object. The reproduction may be, for example, imaged on a cathoderay tube or radiation sensitive semiconductor such as a Charge CoupledDevice, e.g. to give a pixel map or a line-by-line two dimensionaloutput for later analysis. The focusing method may efficiently useavailable radiation and be focused to a different depth of interest.Alternatively, a “sweeping” imaging method can be used in which theobject is swept point by point, which may give more general depthinformation and a sequential output. The sweeping can take place byirradiating the object with broad angle illumination while reception isrestricted to a narrow sweeping spot by shielding or lens focusing.

[0050] A more preferred method is to illuminate the object by a narrowsweeping spot. The narrow sweeping spot may include a thin parallel beamfrom e.g. a laser type of transmitter or a shielded or lens focused spotfrom a divergent radiation source. According to this more preferredmethod, radiation is received from the object by a receiver, which canhave a narrow take-up angle but preferably has wide angle receptionarea. In order to give the imaging result, an arrangement for providingsweeping of at least the narrow spot part should be present. Thesweeping arrangement may include, for example, moving the active elementitself, its shielding or focusing part as mentioned or separatedeflecting parts, such as a mirror, lens or prism.

[0051] A “non-imaging” or integrating system shall be understood as asystem designed to respond with a unified or single signal to the totalradiation received from an area of the object. A non-imaging principlehas the advantage of a strong simplification of the sensor system, bothwith respect to hardware and after processing. Still, with the methodsaccording to the invention, the non-imaging system provides adequatecontrol results and is preferred for most of the present purposes. Anon-imaging system need not have a sweeping arrangement forreconstruction of a two-dimensional image but it is preferred that theactive elements, after any modification as described, providetransmission and reception, respectively, that have a stable axisorientation in relation to the support for the active element. In staticsensing of the container position, the support is fixed in relation tothe container. In scanning between the sensor and the container asdescribed, the axis orientation may still be stable, but the support andcontainer movable in relation to each other, preferably with the sensorfixed and the container movable in relation to a housing as described.All in all, fixed arrangement of the axis orientation and the activeelement support in relation to the mechanism or a housing is preferredfor simplest overall design.

[0052] Although a focused image can be allowed to fall on the receiveralso in the non-imaging method, it has little meaning as a unifiedresponse is delivered. It is generally preferred to allow “de-focused”radiation to fall on the receiver. Then, preferably, at least theradiation from the foremost part of the object, closest to the receiver,and most preferably radiation received substantially from all depths,should be de-focused. This may require that the radiation directedtowards the receiver is out-of-focus convergent, parallel or preferablydivergent. It is also preferred that the transmitter gives offde-focused radiation in the sense that an area covering irradiation isused, such as a wide beam of parallel radiation, an out-of-focusconvergent radiation or, preferably, a divergent radiation. Withpreference, the area or angle covered by the transmitter can be largerthan the area or angle covered by the receiver

[0053] In addition to a valuable simplification of the sensor systempossible, the de-focused radiation method has the advantage of giving aresponse from a substantial space in both width and depth of the object.This principle allows the system to register a composite “fingerprint”response of the object part observed. The fingerprint is not only highlyunique but also highly difficult to mimic, more so if registered in thenonvisible frequency range.

[0054] These advantages are amplified if the area covered by thereceptor is fairly large in relation to the object and if the areacovered is not sharply, but softly or gradually, delimited fromnon-covered areas. As the object type and target part thereof may varystrongly, absolute area values are difficult to provide. A suitablespace angle, with any means for correction present, drawn with itsvertex at a receptor axis base and with its wide end covering thetake-up area, can, for example, be above 10, preferably above 30 andmost preferably above 45 degrees. The angle may be very large but isgenerally less than 180 degrees, preferably less than 160 and mostpreferably less than 140 degrees. The take-up area is commonly andpreferably circular but when not, these values relate to a circular areaof the same size as the actual value.

[0055] Selection of hardware depends on which of the above sensor systemprinciples is chosen. As indicated, a sweeping spot can be obtained by ashielded divergent source, better by a lens system or a laser typedevice. A parallel beam can be obtained by a collimator lens system or alaser type device. A divergent beam can be obtained with a plain diffusetransmitter for simplicity or a lens system for best control. Similarly,the receiver reception angle can be adjusted by shielding but better bya lens system for control and energy efficiency.

[0056] Between transmission and reception, the radiation shall beaffected by the object, which can take place in a multitude of ways.Generally, the phenomena at play are reflection, transmission,absorption and scattering. For example, radiation encountering a changein refractive index for the radiation frequency used will be reflectedto a higher or lower extent. The reflection may be diffuse ifirregularities are present or may otherwise preserve a wave front andresult in an imaging mirror type of reflection. Radiation not reflectedmay be transmitted through the surface and possibly refracted. Passagemay then cause absorption, roughly exponential energy fall off withtransmission length. The absorption, like the reflection, may be diffusewhen irregularities are present or otherwise imaging. Scattering may becaused by diffuse reflection and transmission.

[0057] The degree to which these phenomena affect the radiation may bestrongly frequency dependent, which can be used to amplify desirabledifferences. In principle, this can be done at two extremes. Either anarrow bandwidth or even monochrome radiation is selected at thefrequency, maximizing the effect desired. A narrow bandwidth can beobtained by filtering out, through absorption or refraction, a singlefrequency from a basically broadband radiation source. The filtering maybe carried out utilizing a laser type of transmitter, emission spectrabands or any other method.

[0058] One advantage of narrow bandwidths is high signal-to-noise ratiosand less influence from random background radiation. Another advantageis that either the transmitter or receiver component can be selected ofsimple broadband type since the output is still determined by the singlecommon frequency. A specific advantage is that a spectroscopic analysisof, for example, a container content is possible. This may requiremeasurement of more than one single frequency or single frequencies overa range, such as establishing an IR spectra over the component. Afurther advantage is the possibility to detect a frequency changeintentionally introduced for marking purposes, such as a fluorescence.

[0059] At the other extreme, a broadband radiation can be used,preferably by selecting broadband components for both transmitter andreceiver. Broadband components, such as lamps, light emitting diodes andphotodiodes or phototransistors, are readily available, cheap and energyefficient. Broadband radiation further allows more objectcharacteristics to affect the radiation. For example, an analysiscorresponding to color analysis in the visible region can be conducted.In most applications, a broadband approach is preferred. A suitablewidth is then at least a variation coefficient of 1 percent, preferablyat least 5 percent and most preferably at least 10 percent, plus andminus the nominal frequency, defined at the frequency where the levelhas fallen to less than 30 percent of the maximum level.

[0060] The radiation may be affected by the above-described phenomena atseveral parts of the objects. Besides an area covered by the transmitterand receptor, the influence may take place at different depths of theobject, such as the two surfaces of the front container surface, thecontent of the container and the two surfaces of the wall of the otherside of the container, possibly repeated in any casing surfaces, as wellas at any crack or other irregularity in these parts. Alternatively, theradiation may be blocked at a first surface by a barrier to theradiation, such as metal for optical and infrared radiation. Similarly,the radiation may be affected by repeated reflection or repeatedscattering, e.g. from the container or a surrounding housing, such as acavity filling diffuse radiation. It is also possible to introduceactive measures for creating detectable differences. For example, thehousing part may be provided with a characteristic distinctive to thecartridge part to allow detection of the container presence.Alternatively, a particular functional part of a container or cartridgemay be marked for detection. For example, one part may be designed toreflect radiation and another part to absorb radiation. As an example,for visible or infrared electromagnetic radiation carbon black can beused for absorbency and metal or titanium oxide as reflective materials.

[0061] A further degree of freedom is the relative positioning of theactive elements, both in relation to each other and the active elementsin relation to the object. For the sake of description, the transmittershall be described with reference to its main beam axis, being thecentral axis, symmetry axis or axis of maximum intensity as the case maybe, after the beam has been given a directionally by shielding, a lenssystem, etc., when present. Similarly, the main receptor axis of thereceptor shall be its central, symmetry or maximum intensity uptake axisafter possible correction by shielding, lens systems, etc. An axis planeshall be understood as a plane in which the axis lies.

[0062] Assuming first that both the transmitter axis and the receptoraxis lie in the same plane, they can form a variety of angles withrespect to each other. Both can point in substantially the samedirection with substantially parallel axes, i.e. with about zero degreesangle between the axes, as with a transceiver type of active element.This arrangement is advantageous when concentrating on reflectedradiation from the object but can also be used for transmitted light ifthere is some reflection within or behind the object, e.g. by aninstalled mirror type surface.

[0063] The active elements can be placed oppositely so that thetransmitter beam is directed into the receptor uptake axis, i.e. withabout 180 degrees angle between the axis. This arrangement isadvantageous when concentrating on radiation transmitted through theobject, for example when absorption is a main parameter to be detected.The receptor can be placed anywhere between the abovesaid extremes, toform any acute or obtuse angle between 0 and 180 degrees, such as about90 degrees, to the transmitter axis. This arrangement may beadvantageous when concentrating on detection of scattered radiation fromthe object, for example to detect impurities or unclarity. It ispossible to arrange several active elements around the circle defined byrotating the receiver axis 0 to 360 degrees in relation to thetransmitter axis in the above exemplified way. For example, with one ormore transmitters, it might be of interest to position one receiver atabout zero degrees, one at about 180 degrees and one at about 90 degreesto obtain three signals maximizing responses for reflected, absorbed andscattered radiation respectively, which can be of interest to obtain amore detailed object fingerprint or to make possible corrections for thevarious response components in the radiation received, e.g. eliminationof influence from scattered radiation.

[0064] It has been assumed above that both the transmitter and thereceiver axes are in the same plane, which is not necessary althoughgenerally optimal for strongest response. Space restrictions may requirethe planes to be slightly displaced although still substantiallyparallel. The planes may also form an angle with respect to each other,which may be useful to utilize available space or to obtain asemi-transmitted or semi-reflected response from large object, such asalong a cartridge axis.

[0065] It is possible to make the active elements movable in relation toeach other and provide means to perform such movements, e.g. to obtain atomographic-type scanning of the object, to allow a single activeelement to perform the action of several or to superpose a dynamiccomponent to a static measurement to facilitate or improve on signalprocessing. In most applications, it is, however, sufficient andpreferred to arrange the active elements mutually static for simplestdesign. As indicated above, it may also be of interest to allow for arelative movement between the active components and the object, whichcan be done by arranging the active elements movably in relation to thedevice but preferably by making the object movable in relation to thedevice. Scanning speeds can be selected within broad limits and, forexample, be determined with other than sensor considerations, such asthe earlier suggested for cartridge movements. It is an advantage thatlow speeds can be used, even zero speed in the case of stationarymeasurements.

Sensor Applications

[0066] As indicated, the sensor system can be utilized to readinformation generally in the form or a machine readable marking. Thesensor system may also detect physical functional properties of theobject observed. A marking may also serve to facilitate detection of afunctional property, such as a marking of a critical object position.For the purposes of the present invention the object “properties” fordetection shall be understood to incorporate all these possibilities.

[0067] The nature of the information transferred by a machine readablemarking system can be of any kind and is not limited for the principlesof the invention. For the preferred medical delivery device applicationsuch information may be of general nature, such as security codes,patient codes, administration schemes, calibration data, etc. The datamay be in some way related to the container, such as container type orsize identification, stroke length or needle type for cartridges,content preparation type, volume and/or concentration, distributiondata, batch number, storage capacity, temperature sensitivity,expiration dates, classification according to official standards, etc.The information may be used for a variety of purposes, such as simpledisplay of the information to the user, setting of processor parameters,basis for acceptance or rejection of attached container, enabling ordisabling device operation in response to patient data and securitycodes, selection or downloading of administration pattern, calculationof doses, etc.

[0068] In order to obtain the advantages stated with respect to readingmarkings, it is preferred to use a non-imaging sensor system, as definedherein and most preferably a de-focused radiation method as definedherein. Preferably, the receptor has a divergent take-up angle forreceived radiation, which may have a space angle of, for example,between 10 and 150 degrees, better between 20 and 120 degrees, and mostpreferably between 30 and 90 degrees. The area covered on the marking bysuch a reception can still be controlled by the distance between thereceptor and the marking. In order to concentrate the marking area thedistance typically is less than 25 mm, preferably less than 15, and mostpreferably less than 10 mm. A certain area size is desirable to even outfluctuations and to permit even irradiation. Preferably, the distance isabove 0.1 mm, more preferably above 1 mm and most preferably above 2 mm.The shape of the area covered by the receptor may vary due toirradiation restrictions, geometry of receptor or its shielding and anycurvature of the object itself. Indicative of the absolute size of thearea covered, expressed as the diameter of a circle with correspondingsurface, may be between 0.1 and 20 mm, preferably between 0.5 and 15 mmand most preferably between 1 and 10 mm in diameter.

[0069] The information is carried by detectable differences in any ofthe possible optical properties discussed above. The area covered by thereceiver will generally give a unified and accordingly integratedresponse. It is hence possible, that the abovesaid area size covered bythe receiver at any time is non-uniform. For example, the area sizecovered may have a gradient but preferably then a grid or raster patterne.g. as used in printing and graphics. However, preferably the areacovered is substantially uniform to the radiation used. Even if it ispossible that the marking covers only a part of the receiver coveredarea, it is generally preferred for strongest response that the entirearea is marked.

[0070] Because of the analog response, it is possible to have amultitude of detectable information levels from a single marking area.These information carrying levels may form a truly analog signal bybeing designed to cover a continuum of possible levels, for example torepresent an equally truly analog characteristic,. such as containercontent volume or concentration, e.g. by being represented between fullreflection/transmission and full absorption. It is often preferred forsignal treatment reasons to design the marking system to give a multipleof discrete information level responses for simple after processing,i.e. a digital system. Because of the many levels detectable, such adigital system shall preferably not be binary but based on more than twodifferent levels, preferably at least three and most preferably morethan three discrete levels, for example hundreds of levels. In order tofacilitate binary digital after processing of the signal output, it maybe beneficial to adapt the multitude of possible levels to the binaryscale and to design the radiation detectable levels of the marking forexample to any 2^(n) value with n larger than 1 such as 4, 8, 16, 32,64, 128 or 256 discrete levels.

[0071] In spite of the amount of information possible to extract from asingle marking area spot, it may be desirable to include several suchinformation area spots in order to repeatedly multiply the possiblecombinations. Even if it is sufficient in a specific application withthe alternatives from one area it may be beneficial to include a controlarea, preferably with another level. Accordingly, it is preferred to usemore than one area. In a truly analog system design, such a multitude ofareas may form a continuous gradient. Preferably, however, the areas areseparated to give a step difference when read in sequence, possibly withstandard level surfaces separating each information carrying area tofacilitate discrimination between areas. The individual areas in such aset may be read by a number of individual receivers, although it ispreferred to use a single receiver, or a few for control, for scanningthe set of areas by relative movement according to any of the mechanismsearlier described. Scanning may take place statically or semi-staticallyby moving the receiver to an area and recording its level or preferablyby continuously moving the receiver over the areas to get a dynamicallychanging response, or by a combination of these methods.

[0072] The marking can affect the radiation in any of the generalmanners described such as by differences in reflection or scattering butpreferably differences in absorption is employed. It is often sufficientto use differences in the total absorption over the bandwidth used,disregarding any frequency dependence, preferably by using adsorbentsaffecting all frequencies in the bandwidth used about equal, whichallows for the simplest signal processing and permits use of monochromeradiation. Alternatively, or in addition, adsorbents altering thefrequency distribution can be used to create a correspondence to colorsin the visible range, which strongly increases the number ofcombinations.

[0073] The frequency differences may be detected by a receiver able totune the various bandwidth frequencies or preferably by using more thanone receiver sensitive in different bands. Differences in absorption canbe detected in transmitted radiation, by use of pigments or preferablydyes. However, the differences are preferably detected in reflected orscattered radiation, such as by placing transmitter and receiver closethe same side of the marking.

[0074] Although it is possible to arrange the marking over some otherobject feature to have a combined response therefrom, it is generallypreferred to isolate the marking response from other influences and, forexample, use an opaque or preferably reflecting backing behind themarking, such as a metal sheet. As described herein, a suitable pigmentsystem in visible and infrared regions is carbon black and titaniumoxide, having a fairly uniform influence over a broad frequency range.The marking may be directly applied to the object for example byspraying or painting. Alternatively, the marking may be indirectlyapplied by using a label or sticker, allowing common printing methods tobe used and facilitating application of backing materials.

[0075] In a medical delivery system, the marking principle can, forexample, be used to provide a set or system of at least two andpreferably more containers, having different properties in at least somerespect, and to provide the containers with a machine readable markingof the nature described herein that is designed to carry informationallowing discrimination between the different container property types.The container may, for example, be different with respect to preparationtype, concentration, volume, size, cartridge diameter, security code,expiration dates, etc. Generally, the marking would allow machineidentification of container type for any purpose, such as for rejectingcontainers with passed expiration dates, making the connection between aspecific security code and a specific patient or machine screening,selection or sorting of containers for any of its properties e.g. inmanufacture, distribution or stock holding. Commonly, the container willalso be similar in some respect, such as any of the above mentioned.Preferably, the containers are similar in the respect that they areadapted for use in the same medical delivery device, such as by havingsimilar features for connection to the attachment means, sizes adaptedfor use in the device and a geometry adapted for reading of its markingby the same sensor system. This will allow the device, for example, toreject containers not intended for use and to adapt to container typesallowed.

[0076] Marked information may be delivered to the device in any way, forexample, via a sensor arranged to receive such information specificallyfrom a separate information strip or via a marked dummy container. Forthe greatest security, it is preferred to deliver the information to thedevice via a marking physically attached to the container, at least ifthe information in any way is related to the container as described.

[0077] As such, the sensor system may also be used to detect afunctional property of the object. Contrary to the “marking” describedabove, a “functional”, property shall be understood as anycharacteristic of an object not applied to transfer information to thedevice but is present for the intended operational purpose of the deviceor is the result of the object manufacturing or use history. In thepreferred application of medical delivery devices, sensing of afunctional property normally serves the purpose of determining orverifying adequate status of the container to be used, e.g. to allow thecontrol system to accept or reject the container or to adapt to itsspecific conditions or status or to monitor a process taking placetherein. The functional property is generally a physical property of thecontainer or its content and, as such, difficult to falsify. Yet forsafety reasons it is important that the detection is fail-safe.

[0078] In order to establish whether or not the functional property ispresent at a container type object the container position is irradiatedand the affected radiation is received and compared with a predeterminedrepresentation of the characteristic to be detected. Normally, thecontainer is in the container position but it might also be absent, forexample when the system searches for a non-present cartridge, when acalibration signal for the position as such is to be determined or whenmeasurement against a dummy is made. As a physical property is difficultto falsify, any kind of radiation sensor system principle can beutilized. An imaging system, also in the visible range, can be utilized,for example to detect a contour part of the cartridge or a discontinuityin the container or content signaling a defect or impurity when comparedwith a representation of the proper condition. It is often preferredhowever to utilize a nonimaging system or most preferably such a systembased on defocused radiation in order to exploit the general advantagesinherent therein as described, e.g. to obtain unique fingerprint ofseveral radiation type contributions or to combine in a simple system ofhigh security able to sense both marked information and functionalproperties. Although functional properties are then detected by aresponse dependent on radiation received from different depths, it ispreferred to receive radiation from about the same response angles andareas as stated for general or marked information use, if given as thearea of container part closest to the active elements.

[0079] It may also be beneficial to combine functional property sensingwith a relative movement between the receiver and the container, forexample, to obtain the dynamic response signal earlier described, tosense, in sequence, both marked information and functional properties orto detect several different functional properties, or the variation of asingle property, along a container, for example along the axialextension of a cartridge type container. Movement of the container mayalso be part of a dynamic process to be monitored by the sensor systemsuch as an emptying, filling, dilution or dissolution process or any ofthe above-described initiation steps for a cartridge type container. Anydynamic process can be followed either statically with the container andreceiver mutually fixed or dynamically with a relative motiontherebetween. Below some examples of various sensing options.

[0080] A contour part of the container may be sensed to verify if acontainer has been inserted in the device, that it has the intended sizeand that it is properly positioned for example in relation to theattachment means or its preset position if movably arranged. A highlyspecific contour part, such as a flange or closure part may be selectedif an imaging sensor system is utilized. A non-imaging system can beused to detect the relative position of the contour. The response can behighly sensitive to even small positional differences if the receptionangle is small compared to the displacement to be detected and if thecontour is normally located within the angle area. If several orthogonalcontour lines are detected, the entire container position will be welldetermined.

[0081] Internal features may be detected provided the container istransparent to the radiation. In particular, it may be beneficial todetect a movable wall, especially a plunger in a cartridge typecontainer. Detecting a movable wall way may, for example, permitverification of a fresh container by confirming that the piston is inits start position. Completed initiation, such as reconstitution ordeaeration, may be verified by confirming the required displacement ofthe plunger or contact between plungers in multichamber systems,determining doses left in the container from a sensing of currentplunger position or emptied container by verified end position.Preferably, sensing can take place by the absorption of the plungermaterial itself, optionally modified e.g. with an added absorbent, andpreferably in reflected radiation. The uptake area should be adapted tothe plunger size, preferably so that it covers only a part of its axialextension making it possible to detect details thereof, such as sealingrings, even in non-imaging or de-focused radiation. With preference, acartridge for this purpose can have a plunger position exposed forsensing and marking carrying information at another part. The marking isreadable in non-imaging radiation and accordingly allows sensing forboth purposes by the same system.

[0082] Also, the internal container content can be sensed. Presence of asolid can be detected by its absorption or scatter and the presence of aliquid can be distinguished from a gas by the difference in refractiveindex, for example, in transmitted radiation at an off-center line wherethe difference in refraction provides a detectable response difference.Also, impurities in an otherwise homogeneous media, e.g. liquid or gascan be detected, such as unclarities or miscolorations or gas orparticle inclusions by increased scatter or total absorption change froma small uptake area. Similar methods can be used to detect deficienciesin the container walls, such as cracks or deformations. Preparation typecan be chemically verified by measurement at spectral wavelengthstypical for the product. Marking or modifications may be used tofacilitate or amplify the response at detection of functionalproperties. For example, instead of determining a container position onthe basis of a physical structure thereof, a marking on at least one orpreferably several spots on the container or label may serve the purposeof defining the container orientation. Verification of containerpresence can similarly be done by the detection of a predeterminedmarking. A modification may also take the form of an attached mirrorreflecting part on the container or a prism reflecting or refractingfacet thereon, preferably arranged to divert transmitter radiationtowards the receiver.

[0083] Although the invention has been described in relation to deliverydevices it is clear that the system principles can be used for anysimilar or entirely different purpose. For example, the marking systemhas a general utility and is not restricted to marking of containers butmay be used on any article or for any information transfer purpose. Thesensor for reading such a marking must not be included in a deliverydevice but can be included in any other device or in a general purposereader. Similarly, the general principle of detecting a functionalproperty by its radiation fingerprint need not be restricted toproperties of containers but can have a general utility for otherarticles. For example, the utility may detect their presence, position,appearance, structure at the surface or at depth similar to any of theabove-described applications. Also, the sensor be included in anyidentification system. Accordingly, the system may be used as a generaldevice or method for analysis of an object, e.g. for color analysis atany frequency range or for surface or depth structure or textureanalysis of any object.

Signal Processing

[0084] Processing of the signal received from the receiver can takeplace in any processor located anywhere, for example, to continuously orintermittently by intermediate storage transmit the signal to a remotecomputer for processing in real or artificial time. Preferably, thesignal is fed to an on-board microcontroller of the device and, in mostinstances, it is also preferred to process the signal in real time. Theprocessing will be described in terms of these options.

[0085] The signal processing for the sensor system will be differentdepending on which system principle is utilized. A system based on animaging sensor system may require signal processing able to make aconnection between receiver individual pixel responses in space or timeto a specific point in space, which may require parallel processing ofall pixel responses, connection of each pixel response to an absolutegrid address, synchronization of line sweeping to absolute startpositions, etc. signal analysis may then incorporate any known systemfor image analysis, e.g. by comparing the signal with a predeterminedrepresentation of the object property to be detected.

[0086] In the preferred embodiment of a non-imaging system, signalprocessing can basically be kept very simple. The transmitter can bemade to give off a stable radiation and the receiver to receive partthereof. The output from the receiver may be a stable level response,such as a stable voltage, for example when the object is non-changing orwhen there is no relative movement between receiver and object, wherebya substantially “static” response is relied upon. The predeterminedrepresentation of the property to be identified can then similarly be alevel and the process of comparison may include any algorithm forcomparing the measured level with one or several predetermined levels todetermine whether or not the sought property shall be deemed present.Preferably, the response is measured several times or over a certaintime to average out any small disturbances or variations.

[0087] A more reliable measurement can be obtained when detecting andcomparing more than one part of the object, preferably parts withdifferences in response levels. Hereby, “relative” rather than“absolute” levels can be determined by comparison which, among others,improve reliability. Relative measurements can be made in a“semi-static” method by making more than one static measurement ondifferent object parts. At sensing of marked parts, several markings,including separate reference levels or constituting mutual referencelevels, can be read and used to establish response level differences.Similarly, when sensing a functional property, more than one measurementcan be done at the site of interest and at another site, e.g. at aplunger position and a plunger absent position or at filled and emptycontainer parts, or at two points of different responses at the sameobject, e.g. at plunger sealing rings and therebetween, respectively.Alternatively, or in addition, a relative measurement can be based ondifferences in radiation responses at different wavelengths, if present,at the same object area. The signal processing may here incorporate anestablishment of the response difference or ratio between the sensedparts and comparison of this relative level between one or severalpredetermined level differences or ratios.

[0088] It is generally preferred to include a “dynamic” action to thesignal, i.e. to provoke a signal changing over time and in some wayrecord and act on the response in the same way as the semi-static methodalthough with more data available for elimination of random factors. Adynamic method also generally permits extraction of more information forcalculation and decision making owing to the time axis present, such asrate of change or floating average or noise level calculations. Signalprocessing here may include comparison with a sequence of relativelevels to be confirmed, possibly independent of time, or a more completecurve fit for more elaborate analysis. A dynamic response can be causedin several ways. A continuous change in sensor system frequency maycause a varying response. A monitoring of a dynamic process, such as thedissolution of a compound or the movement of a piston, can be followedover time. As indicated, a preferred dynamic response is caused by arelative movement between object and sensor, which may serve both toread a sequence of markings and several different object functionalparts along the movement track or several details along the same objectpart giving a more detailed fingerprint thereof.

[0089] The above-described dynamic method, wherein receiver output ismonitored for its amplitude versus time function, directly orindirectly, and the function processed before an activity is basedthereon, is highly compatible with existing processor technology. Thefunction may be obtained and treated as continuous, but it is preferredthat values are sampled from the device output, which may be made atirregular but preferably at regular time intervals at a certainfrequency. Sampling can be in any of several known ways. The samplingmay be digital in the sense that the amplitude is compared with areference level and either set to a binary 1 or a binary 0, depending onwhether the amplitude is above or below the reference level, which maybe varying but preferably is fixed. Among other methods for extractingmore information from the raw data, an analog sampling method isgenerally preferred, in which the function absolute amplitude value isrepeatedly registered. The analog value can be processed in an analogprocessor but it is mostly preferred to convert the value to digitalform and process it in a digital processor. The signal may in a knownmanner be filtered to remove certain frequency ranges.

[0090] The signal processing may include a function comparable withautomatic gain control, either by hardware or by software, meaning thatsystem amplification at the response level of interest is adapted to thepresent purpose of either overview or magnification.

[0091] The function values may be memorized and processed at any timeand rate but real time processing is generally preferred in mostapplications, which may still require some memorizing of the values tobe simultaneously processed at any given time. It is preferred that theprocessing involves at least two, preferably three and most preferably amultiple of function values at a time.

[0092] In all of the above discussed signal processing methods, it ispossible to use several transmitters and receivers at a time. This maybe done for any of the reasons earlier discussed, such as collection ofradiation from different angles to allow calculation of a correctedresponse. Specifically, for the now discussed objects it may be ofinterest in the static method to use several receivers to sensedifferent object parts, in-the relative measurement method additionallyto simultaneously sense the levels on which the relative measurementsare based or to collect responses at several frequencies and in thedynamic method additionally to cover several aspects of the processmonitored.

[0093] In any of the methods discussed, it is also preferred to modulatethe transmitter signal and to detect the modulation at the receiveroutput signal. This is in order to exclude influence from random factorsand disturbances not having the modulated characteristic. A highlyadvanced modulation can be used although it is often sufficient tosuperimpose on the radiation a stable modulation frequency. Such afrequency should be clearly above the ubiquitous power line frequencieswith overtones. For example, the frequency can be above 0.5 kHz andpreferably above 1 kHz. However, the frequency can be kept below 1000kHz and preferably below 100 kHz. The receiver system should be tuned tothe modulation frequency as narrow as possible, but can have a smallbandwidth in case doppler shifts are to be detected. Filtering of thesignal can be made with any known method based on hardware or software.

[0094] The above exemplified signal processing steps shall not excludeany other type of common processing. In particular, any processing mayrequire normal initializing steps, such as zeroing of the system bymeasurement of the background radiation immediately before insertion ofa container or normalization against a standard dummy container orreference marking absorbency level.

[0095]FIG. 1a and 1 b show in schematic form a cartridge type containergenerally designated 1 and having a cylindrical part 2 and containing aplunger 3 having three sealing rings 4. Attached to the cylindrical part2 is a label 5, assumed to bear coded surfaces on a totally reflectivebacking. A transmitter is indicated at 6, giving off radiation in theform of a wide cone 7. A first receiver 8 is arranged close totransmitter 6 and facing in the same direction and which receivercollects radiation from a cone 9 that is somewhat more narrow thantransmitter cone 7. A second receiver 10 is arranged, relative thetransmitter 6, on the opposite side of the container and facing towardsthe transmitter 6. A third receiver 11 is arranged at about a rightangle relative the transmitter 6 axis and facing towards containerinterior. In the relative positions shown, the transmitter 6 radiationis directed towards the label 5 and the first receiver 8 collectsradiation reflected from the label part irradiated by the transmitter 6.As the label is not translucent, receivers 10 and 11 do not receive anydirect radiation from the transmitter 6 but may receive random radiationscattered in a housing or entered from the surroundings and theiroutputs may be used to correct the response from the first receiver 8for any such background radiation. If the container is axially displacedso that the plane of active elements becomes positioned at 12, that isbetween label 5 and plunger 3, the response from the receivers will beentirely different. Assuming that the container 1 is transparent, someradiation will be reflected at the outer and inner surfaces of theradiation entering side of the container. Similar reflections will occurat the radiation exit side of the container. Absorption will take placein the walls and possible container content and some scattering willtake place at all these locations. The change in output from thereceivers can easily be detected, i.e. the second receiver 10 mayreceive considerably more radiation than when behind the label. If thecontainer is further displaced to locate the plane of active elements atthe plunger 3, the receiver signals will again change. In particular,the first receiver 8 will record the typical radiation reflected fromthe plunger. This sensing can be static or dynamic if made duringmovement of the container. In the latter case, the difference inresponse at and between the sealing rings 4 may be detected.

[0096]FIG. 2 shows an actual response from a sensor system operating inthe infrared region when passing over a plunger with three sealing ringsinserted in a transparent syringe-type container. The vertical axisgives the response level from the receiver in digitized values between 0and 256 and the horizontal axis lengths in arbitrary units. The threecurves represent the response when measured through transparentfiltering labels being, from above, clear, green and blue, respectively.It can be seen that the differences in response at the three sealingrings of the plunger are clearly detectable, even when the filteringlabel has a color closely resembling the color of the plunger material,as in the lowermost curve.

[0097]FIG. 3 is a block diagram over the main functions in a suitablesensor system according to the invention. A microcontroller 31 activatesand deactivates the transmitter 34 over a modulator 32 and amplifier 33to give a 3 kHz varying output from the transmitter having a nominalwavelength of 940 nm. The radiation hits and is affected by an objectsurface 35 and part of the radiation is collected by the receiver 36.The output signal from the receiver 36 is filtered in a bandpass filter37 to extract frequency components narrowly around the 3 kHz modulationfrequency. This signal is amplified in 38 and fed to an A/D converter 39and the digital output is returned to the microcontroller 31. Based onthe signal received and on comparison levels of interest themicrocontroller 31 may activate an automatic gain control unit (AGC) 40to deliver a reference level to the A/D converter to permit a shift ofreference level and level range resolution for the digitalization. Themicrocontroller may have access to software for bandpass filtering, theAGC function and, for example, cluster analysis for comparison ofreceiver response with predetermined characteristics to be identified.

[0098] The circuit of FIG. 4 is basically composed of three parts, apower supply part shown at the lower section of the drawing, an analogradiation part shown in the middle section and a digital processing partshown at the top. The radiation signal for the LED transmitter ismodulated from the processor U4 (pin 28, “s”) via the transistor Q1 ofthe transmitter diode D5 (TSMS3700). The radiation from the objectimpinges on the photo diode receiver D4 (BP104FS) and is transformedinto a current. The radiation part further comprises double filteringand amplifier steps where the filters are of bandpass type, i.e. eachfilter includes both a low pass and a high pass filter. The signalenters the high pass filter C8, R23, R24, is amplified in U2A and entersthe low pass filter C10, R25, R26. The procedure is repeated in highpass filter C9, R22, amplifier U2B and low pass filter C11, R27, R28.After these analog steps, the signal enters the A/D converter, beingpart of the microcontroller U4. The signal is processed in digital formin the microcontroller U4 by use of software, e.g. digital filtering,sorting and comparing algorithms, etc. The resistors R4 to R11 acttogether with the microcontroller as an AGC function, allowing detailedanalysis of different amplitude levels.

[0099]FIG. 5 shows a simple label with markings to be used on acartridge type of container, for example, as illustrated in FIG. 6. Thelabel 50 has a first large uniformly colored area 51 with predeterminedabsorption, which is intended to be read statically, i.e. when the areais kept fixed in relation to the sensor. The absorption level of thesurface may bring information about the cartridge type, content orconcentration or may be used for calibration purposes. Field 52 is awindow in the label which window is entirely clear and transparent andwhich window is intended to allow sensing of cartridge interior andespecially the presence of a plunger. Fields 53, 54 and 55 are againuniformly colored areas of preferably different absorption levels thatcarry information of, for example, the same type as area 51. The window52 and the fields 53, 54 and 55 are intended to be read dynamically insequence under relative movement between label and sensor as indicatedby arrow 56. A sensor is indicated in phantom lines at 57 in a firstposition over the static field 51. After reading of this field, thecartridge with the label is moved in direction of arrow 56, which willcause window 52 and fields 53, 54 and 55 to pass across the sensor 57 toproduce a response versus time function processable by electronics. Itis assumed that all label surface except the window 52 is substantiallynon-transparent, by sufficient pigmentation or an opaque backing, to beunaffected by radiation from behind the label.

[0100]FIGS. 6a to 6 d show schematically four operational stages of apump part 60 and a dual-chamber type cartridge 70. The pump 60 comprisesa housing 61, a piston rod type member 62 and an electromechanical unitgenerally designated 63 operable to actuate and control the rod to bothmove the cartridge 70 and expel its contents. With preference, thesepump parts are constructed according to the above referenced co-pendingapplication. A sensor 64 is arranged at the intended cartridge positionof the pump 60. The cartridge comprises a barrel 71, an outlet 72, arear plunger 73 and a front plunger 74. On the barrel outside isattached a label for example as described in FIG. 5.

[0101]FIG. 6a shows the relative positions of pump 60 and cartridge 70when the cartridge has just been attached to the pump with the pistonrod 62 close to the rear plunger 73. The sensor 64 is located at therear plunger 73 and over a first part of the label 75, for example thestatic field 51 of FIG. 5, which label part is read by the sensor 64.

[0102]FIG. 6b shows a position in which the unit 63 has caused thecartridge 70 to move towards the pump part 60 while concurrentlyabutting the rear plunger 73 to maintain its absolute position.Accordingly rear plunger 73 is still at the sensor 64 but the label 75is supposed to have traveled to a position where window 52 is betweensensor 64 and plunger 73. The sensor can now verify proper plunger 73position and characteristics through label window 52.

[0103]FIG. 6c shows a position when unit 62 has caused the cartridge tomove still further towards the pump under movement of the plunger 73 toa position within barrel 71 where it is in contact with the frontplunger 74, and perhaps the two plungers have moved a certain distancetogether, and the cartridge is in its final position relative the pumpunit 60. Under this cartridge movement the remaining parts of label 75have passed the sensor 64 to enable a dynamic reading of fields 53, 54and 55 and extraction of any information encoded therein.

[0104]FIG. 6d shows a position wherein unit 63 has caused member 62 tomove forward to expel the cartridge content in front of plunger 74through outlet 72. Under this operation sensor 64 may monitor thedisappearance of plunger 73, proper clearance of barrel 71 and detectionof a marking on member 62 signaling arrival at its forward extremeposition.

[0105] The exemplified embodiments are illustrative only and shall notbe understood in any way limit the scope or generality of the inventionas defined in the claims.

1. A preparation delivery device comprising a) a container for thepreparation having or being prepared for the arrangement of an opening,b) a mechanism operable to deliver at least part of the preparation inthe container through the opening, c) attachment means for connection ofthe container to the mechanism and d) a sensor system arranged to detectat least one predetermined property of the container or its content,characterized in the improvement comprising a radiation transmitterarranged to irradiate the container position or a part thereof, aradiation receiver arranged to receive at least an area part of theradiation from the transmitter after the radiation having been affectedby the container position and the receiver being designed to give anoutput response representative for the total radiation received fromsaid area part.
 2. The device of claim 1, characterized in that at leastpart of the container is translucent or transparent at the radiationfrequency.
 3. The device of claim 1, characterized in that the containeris a cartridge comprising a) a generally cylindrical barrel with ageneral symmetry axis and having a front end and a rear end, b) anopening or a preparation for an opening at its front end, c) at leastone displaceable piston inserted in the barrel between the front end andthe rear end.
 4. The device of claim 3, characterized in that thecartridge is of dual or multi-chamber type.
 5. The device of claim 1,characterized in that the mechanism includes pump means actuated byelectric motor means.
 6. The device of claim 1, characterized in thatthe mechanism includes a control system operable to control at least theelectric motor means.
 7. The device of claim 1, characterized in thatthe attachment means include movement means operable to move thecontainer in relation to stationary parts of the mechanism.
 8. Thedevice of claim 7, characterized in that the movement means includescanning means operable to move the container relative the sensorsystem.
 9. The device of claim 8, characterized in that the movementmeans are also operable to perform an initiation operation on thecontainer.
 10. The device of claim 7, characterized in that saidmovement means are arranged to give a speed of less than 10 cm/sec,preferably less than 1 cm/sec.
 11. The device of claim 1, characterizedin that the radiation has a wavelength between 300 and 3000 nanometers.12. The device of claim 11, characterized in that the radiation is inthe non-visible range.
 13. The device of claim 12, characterized in thatthe radiation is in the infrared range.
 14. The device of claim 1,characterized in that the transmitter comprises a light emitting diode.15. The device of claim 1, characterized in that the receiver comprisesa photodiode or a phototransistor.
 16. The device of claim 15,characterized in that the receiver comprises a daylight filter.
 17. Thedevice of claim 1, characterized in that the receiver output isnon-imaging.
 18. The device of claim 1, characterized in that theradiation received is de-focused.
 19. The device of claim 1,characterized in that the irradiation and reception have space anglesabove 10 degrees.
 20. The device of claim 1, characterized in that thetransmitter is arranged to give a divergent beam and the receiver isarranged to have a divergent take up angle.
 21. The device of claim 1,characterized in that transmitter and/or receiver are broadbanded with apreferred frequency variation coefficient of at least plus and minus 1percent of norninal frequency.
 22. The device of claim 1, characterizedin that transmitter and receiver are arranged facing in substantiallythe same direction.
 23. The device of claim 1, characterized in that thetransmitter and receiver are arranged at a distance from the container.24. The device of claim 1, characterized in that the area covered by thereceiver, expressed as the diameter of a circle with correspondingsurface, is between 0.5 and 15 mm.
 25. The device of claim 1,characterized in that the container has a marking readable by the sensorsystem.
 26. The device of claim 25, characterized in that the markinghas more than two discrete levels.
 27. The device of claim 25,characterized in that the marking has several discrete marking areas.28. The device of claim 27, characterized in that moving means arepresent to read the areas in sequence, statically or dynamically. 29.The device of claim 25, characterized in that the marking hasdifferences in absorption or reflection.
 30. The device of claim 1,characterized in that the relative positioning between sensor andcontainer is adapted to detect a functional property of the container.31. The device of claim 30, characterized in that the functionalproperty is a container contour part a plunger position, containercontent or a marking or modification designed to facilitate detection ofa functional property.
 32. The device of claim 30, characterized in thatthe relative positioning is adapted to also read a marking on thecontainer, staticly or dynamically.
 33. The device of claim 1,characterized in that it contains an electronic control unit, preferablya microcontroller.
 34. The device of claim 33, characterized in that thecontrol unit is operative to receive the modified or unmodified outputfrom the receiver and compare it with one or several memorizedcharacteristics and to act differently if and if not, respectively, acertain similarity is present.
 35. The device of claim 34, characterizedin that the control unit is operative to receive a response versus timefunction.
 36. The device of claim 34 or 35, characterized in that saidacting includes the option of activating electric motor means.
 37. Thedevice of claim 1, characterized in that the transmitted radiation ismodulated.
 38. The device of claim 1, characterized in that transmitterand receiver are arranged to have a stable axis orientation in relationto their support.